The Pioneer Anomaly

Radio-metric Doppler tracking data received from the Pioneer 10 and 11 spacecraft from heliocentric distances of 20-70 AU has consistently indicated the presence of a small, anomalous, blue-shifted frequency drift uniformly changing with a rate of ~6 x 10^{-9} Hz/s. Ultimately, the drift was interpreted as a constant sunward deceleration of each particular spacecraft at the level of a_P = (8.74 +/- 1.33) x 10^{-10} m/s^2. This apparent violation of the Newton's gravitational inverse-square law has become known as the Pioneer anomaly; the nature of this anomaly remains unexplained. In this review, we summarize the current knowledge of the physical properties of the anomaly and the conditions that led to its detection and characterization. We review various mechanisms proposed to explain the anomaly and discuss the current state of efforts to determine its nature. A comprehensive new investigation of the anomalous behavior of the two Pioneers has begun recently. The new efforts rely on the much-extended set of radio-metric Doppler data for both spacecraft in conjunction with the newly available complete record of their telemetry files and a large archive of original project documentation. As the new study is yet to report its findings, this review provides the necessary background for the new results to appear in the near future. In particular, we provide a significant amount of information on the design, operations and behavior of the two Pioneers during their entire missions, including descriptions of various data formats and techniques used for their navigation and radio-science data analysis. As most of this information was recovered relatively recently, it was not used in the previous studies of the Pioneer anomaly, but it is critical for the new investigation.Comment: 165 pages, 40 figures, 16 tables; accepted for publication in Living Reviews in Relativit

The interactions of disability and impairment

Theoretical work on disability is going through an expansive period, built on the growing recognition of disability studies as a discipline and out of the political and analytical push to bring disability into a prominent position within accounts of the intersecting social categories that shape people's lives. A current debate within critical disability studies is whether that study should include impairment and embodiment within its focus. This article argues it should and does so by drawing from symbolic interactionism and embodiment literatures in order to explore how differences in what bodies can do-defined as impairments-come to play a role in how people make sense of themselves through social interaction. We argue that these everyday interactions and the stories we tell within them and about them are important spaces and narratives through which impairment and disability are produced. Interactions and stories are significant both in how they are shaped by wider social norms, collective stories and institutional processes, and also how they at times can provide points of resistance and challenges to such norms, stories and institutions. Therefore, the significance of impairment and interaction is the role they play in both informing self-identity and also broader dynamics of power and inequality

Systematic review of information and support interventions for caregivers of people with dementia

Background Dementia is an important health and social care problem and is one of the main causes of disability in later life. The number of families affected by dementia will dramatically increase over the next five decades. Despite the implications for health and social care services in the future, the overwhelming majority of care for people with dementia takes place away from health care settings. Providing informal care for someone with dementia can be psychologically, physically and financially expensive and a range of health service interventions aimed at supporting and providing information to these carers has developed to help carers meet these demands. This review examines whether information and support interventions improve the quality of life of people caring for someone with dementia. Methods A systematic review examining evidence from randomised controlled trials in which technology, individualised or group-based interventions built around the provision of support and/or information were evaluated. Results Forty-four studies were included in the review. Controlling for the quality of the evidence, we found statistically significant evidence that group-based supportive interventions impact positively on psychological morbidity. However, whilst the improvement was unlikely to be due to chance, the clinical significance of this finding should be interpreted tentatively, due to the difficulties in interpreting the standardised mean difference as a measure of effect and the complex aetiology of depression. No evidence was found for the effectiveness of any other form of intervention on a range of physical and psychological health outcomes. Conclusion There is little evidence that interventions aimed at supporting and/or providing information to carers of people with dementia are uniformly effective. There is a pressing need to ensure that supportive interventions at the development stage are accompanied by good quality randomised evaluations in which outcomes that are important to clinicians and carers are measured

Patients and nurses determine variation in adherence to guidelines at Dutch hospitals more than internists or settings.

Contains fulltext : 59148.pdf (publisher's version ) (Closed access)AIMS: To measure adherence to recently developed diabetes guidelines at Dutch hospital outpatient clinics and distinguish determinants for variations in care on hospital, internist and patient levels. METHODS: Thirteen general hospitals with 58 internists recruited 1950 diabetic patients. Data were extracted from medical files (n = 1915) and from patient questionnaires (n = 1465). Multilevel logistic regression analysis was performed to explain differences in adherence rates to the guidelines. RESULTS: Adherence to process measures was high, except for the examination of feet, calculation of the body mass index and patient education activities (the mean of 12 process measures was 64%). Adherence to intermediate outcome indicators was moderate. The mean percentage of patients with HbA(1c) < 7.0% was 23%. Adherence variation on a hospital level was very small (0.6-7.9%), on an internist level moderate (0.4-18.8%) and on a patient level high (74.4-98.8%). Adherence to all process measures and most of the intermediate outcome indicators was highest in the patients seen by a diabetes specialist nurse. DISCUSSION: More focus on patient involvement in diabetic care and the contribution of diabetes specialist nurses may be important factors in improving the quality of diabetes care

Rehabilitation of patients with spinal cord lesions in The Netherlands: An epidemiological study

Very little is known about the occurrence of spinal cord lesions and results of the rehabilitation of patients with such lesions in the Netherlands. This study was conducted to describe the process of rehabilitation in the Dutch situation, to assess the incidence of spinal cord lesions in a regional rehabilitation centre and to characterise differences between traumatic and non-traumatic spinal cord lesions regarding age, level and extent of lesion. In this study 293 patients were included who were admitted to the rehabilitation centre between 1982 and 1993. Sixty-six per cent of this group came from the university hospital. The mean length of stay in the rehabilitation centre was 154 days. After completing the rehabilitation programme 94% of patients went home. Sixteen new SCI patients per million per year were admitted to the rehabilitation centre. Of our group 52% had a non-traumatic lesion, which concerned older patients with more incomplete lesions. In our opinion close collaboration between the university hospital and the rehabilitation centre is needed for optimal rehabilitation. Attention to independent living programmes and appropriate housing facilities can shorten the length of stay and increase the number of discharges of patients to their own environment. For patients with non-traumatic spinal cord lesions special programmes should be made available